Heat oven to 400° F. On a rimmed baking sheet, toss the potatoes, oil, 1 teaspoon salt, and 1/4 teaspoon pepper. Roast until golden and crisp, 45 to 50 minutes.
Meanwhile, in a small bowl, whisk the mayonnaise, lemon juice, garlic, paprika, and 1/4 teaspoon salt. Serve the potatoes with the aioli for dipping.
